Just adding in: Dracula is also out of copyright now, so that name and "look" is fair game. It would in any case be hard to trademark a "look" like Dracula's, which is based on historical outfits of the time. You could just say you followed the same historical model for clothes of the time period. (Likewise, you can write bad Tolkein ripoffs by claiming to draw from the same mythology Tolkein drew from. A fair chunk of fantasy novels do just that. :P ) An outfit like Vampirella's is clearly an invention of the author of the comic, and thus is more likely to come in under "intellectual property" law.